Alice posts a question. Bob posts an answer. I want to comment on Bob's answer, and I want both Alice and Bob to be notified of the comment. Therefore I type something like "@Alice: As @Bob said....".

I then get a pop-up notice that says I can have only one @-sign per comment. Fine. The same notice tells me that the "owner of the post" will be notified automatically, and therefore I should allocate my @-sign to the non-owner. However, I have no idea whether Alice or Bob counts as the "owner of the post". Is "the post" the question or is it the answer?

Question 1: In this situation, who is the relevant "owner of the post"?

Question 2: Can the pop-up text be modified so that other users won't have to ask this question in the future?